Sorry, I thought I had thouroughly searched the threads but obviously not carefully enough. Thanks.

On Windows 8.1 MM8 and a flac library it won't read the track number for tracks 8 and 9 on all albums. MMW reads and plays correctly and shows the tags in the UI. So if an album has >7 tracks, numbers 8 and 9 are shown without a track number at the beginning of the list and then the rest are shown ...